Ammonium Chloride → HCID 9801448, compound

Temperature

32 °C

To a stirred solution of 7-nitro-3-[4-(4-phenyl-1,2,3,6-tetrahydropyridin-1-yl)butyl]-1,2,3,4-tetrahydroquinazoline-2,4-dione (2.1 g) in 50% aqueous tetrahydrofuran (210 ml) was added ammonium chloride (2.68 g) in water (27 ml). To this mixture was added zinc dust (1.65 g) by five portions over a period of 3 hours. The temperature was raised at 32° C. during the reaction. After additional stirring for 2 hours, the precipitated materials were filtered, washed with water and extracted with dimethylformamide (100 ml) under nitrogen. The organic extract was filtered and the filtered cake was washed with dimethylformamide (20 ml). The combined organic solution was diluted with water (24 ml), cooled in a refrigerator, and then treated with active charcoal (1.05 g) and silica gel (2.1 g). The charcoal and silica gel were filtered off and washed with 80% aqueous dimethylformamide (5 ml). To the combined solution was added dropwise cold water (96 ml) with stirring on an ice bath and the precipitated crystals were collected, washed with water, and then suspended in methanol (50 ml). To this mixture was added 10% hydrogen chloride in methanol (50 ml) and the mixture was stirred for 1 hour. The precipitated crystals were collected, washed with methanol, stirred with water, and then filtered and dried to give 7-hydroxyamino-3-[4-(4-phenyl-1,2,3,6-tetrahydropyridin-1-yl)butyl]-1,2,3,4-tetrahydroquinazoline-2,4-dione (0.60 g).

1. filtrationthe precipitated materials were filtered
2. washwashed with water
3. extractionextracted with dimethylformamide (100 ml) under nitrogen
4. extractionThe organic extract
5. filtrationwas filtered
6. washthe filtered cake was washed with dimethylformamide (20 ml)
7. additionThe combined organic solution was diluted with water (24 ml)
8. temperaturecooled in a refrigerator
9. additiontreated with active charcoal (1.05 g) and silica gel (2.1 g)
10. filtrationThe charcoal and silica gel were filtered off
11. washwashed with 80% aqueous dimethylformamide (5 ml)
12. additionTo the combined solution was added dropwise cold water (96 ml)
13. stirringwith stirring on an ice bath
14. customthe precipitated crystals were collected
15. washwashed with water
16. additionTo this mixture was added 10% hydrogen chloride in methanol (50 ml)
17. stirringthe mixture was stirred for 1 hour
18. customThe precipitated crystals were collected
19. washwashed with methanol
20. stirringstirred with water
21. filtrationfiltered
22. customdried

ORD record

ord-ca109dfa020a4b1282c568615b3f064d

Source dataset

uspto-grants-1993_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05264438